There are known pyrotechnic structures including firing bases formed by one or more pieces of thermoplastic material combined together and provided with housings that support the bases of the mortars containing the fireworks, so that they can be arranged at different angles. Typically, the housings are individual cavities open at the base and configured to receive the lower part of the pyrotechnic mortar. An example of this kind of firing bases is shown in document U.S. Pat. No. 5,429,053, in which an elongated body comprises a series of cavities that receive the bases of the mortars containing the fireworks. The support surface of the mortars is convex so that the mortars are placed at different angles.
U.S. Pat. No. 4,222,306 describes a staggered arrangement of mortars that pursues the same goal. Naturally, only tubes of the sane diameter can be coupled together. Additionally, the mortars are not retained by the firing base, and the bases need to be secured to the ground when pyrotechnics of a certain level of power and intensity are fired.
The fireworks mortar battery described in document ES 2330282 proves to be adequately stable with higher firepower; it is formed by a firing base manufactured by moulding plastics with a surface that comprises rails to secure the mortars, so that a plurality of mortars can be arranged in a line and retained by the rails. Subsequent embodiments feature pyrotechnic bases with a curved crosswise section and longitudinal rails for the mortars, which are also manufactured by moulding thermoplastic materials. In order to use them, the firing bases, which are heavier, are arranged with their edges resting on the ground supporting their weight, so that the lines of mortars retained by the rails are placed at different angles in relation to each other.
However, these last solutions described are extraordinarily rigid so that storing, transporting and using them is not only complex but also costly.
FR 2715998 discloses another system for launching several units, each of them equipped with a launch tube and provided with coupling elements on two opposite sides of the tube, which allow the bases to be joined together in order to form a unit and at the same time achieve a relative angular relationship between them, so that two launch tubes can be rotated between them. The tubes can be of different sizes. This system is also complex to manufacture, assemble and use, in addition to being extremely costly.
Other attempts have been made to reduce the size of these pyrotechnic structures. Thus, U.S. Pat. No. 6,851,371 describes a fireworks launching device comprising a support base on the ground that incorporates a mortar support structure and hinged wings that are folded when the device is transported, and unfolded when it is launched, which also comprise security mechanisms that prevent the wings from folding when the base is in use in order to ensure the safety of firing the device.
However, the inherent problems of incorporating mortars of the same or different diameters on a mortar support platform have not been addressed, and neither have the problems of positioning and holding the device in an adequate vertical position all along its length and width.